Chinenfabrik fur schuh and lederindustrie



(No Model.)- 5 I 2 SheetsSheet 2. P. GOHRING.

SEWING MACHINE. No. 521,855. 5 Patented June 25, 1894.

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PAUL GGHRING, OF QBER-URSEL, ASSIGNOR TO EISENGIESSEREI AND MAS- OHINENFABRIK FUR SGHUH AND LEDERINDUSTRIE, VORMALS MILLER & ANDREAE, OF BOOKENHEIM, NEAR FRANKFORT-ON-THE-MAIN, GERMANY.

SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 521,855, dated June 26, 1894.;

Application filed September 8, 1892. Serial No. 445,875. (No model.) Patented in Germany July 21, 1892, No. 69,735; in France August 29, 1892, No. 223,944, and inEugland August 30, 1%392,No.1l5,528.

To all whom it may concern.- Be it known that 1, PAUL GGHRING, asnbect of the King of Wurtemberg, and a resident of Ober-Ursel, in the Province of Hesse- 5 Nassau, Germany, have invented certain new and useful Improvements in Machines for Sewing Boots or Shoes, (for which Letters Patent of Great Britain, No. 15,528, dated August 30, 1892 Letters Patent of Germany, [0 No. 69,735, dated July 21, 1892, and Letters Patent of France, No. 223,944, dated August 29, 1892, were issued to me,) of which the following is a full, clear, and exact specification. My invention relates to lock-stitch sewing machines for sewing boots and shoes and mo re particularly to the kind having an oscillating awl piercing the sole from below, and a hooked needle above the same, so that the sole may be sewed on its whole circumference without removing the last; and my invention consists in several novel devices the conjoint object of which is to secure a steadier and more reliable working of the machine.

The general construction of the machine is 2 5 the same as described in Letters Patent No.

375,244 and my present invention is an improvement of the said patented machine and its various details, when used together in the manner which I am about to describe, corn- 30 bine to make a machine much more practical and of much greater value than the machine described in said Letters Patent.

It relates to the means hereinafter described whereby the presser foot is allowed to 3 5 automatically adjust itself to the thickness of the sole and is then clamped so that what: ever the thickness of the work, it will be securely held between the presser foot and the work supported while the work is being pierced by the awl and needle.

My invention will be. more readily understood by reference to the accompanying drawings, in which- Figure 1 is a front elevation of my improved sewing-machine. Fig. 2 is a side elevation of the same, partly in section; Fig. 3 a plane view of thesame,'showing chiefly the means for imparting motion to the thread-guide;

Fig. 4 a detail view of the presser-foot and its 7 operating lever.

Similar letters denote similar parts through out the several views. a is the main shaft of the machine, and b the shaft around which the awl-carrying head 0 and the needle-carrying head d oscil- 5 5 late. On the shaft b there is-loosely mounted the lever e, carrying at its front end the presser-foot e, and having a spring f, secured to its rear end, the other end of said spring being fixed to the frame of the machine. I may of course substitute a weight for the spring f. The rear end of the lever e is arc-shaped, as shown. Close to the lever e, and laterally of the same, there is another lever g, likewise loosely mounted on shaft 17, and carrying a roll g at its end, said roll working in a cam-' shaped groove 9 provided on a disk 9 which rotates together with the main shaft a. This lever g has a lateral extension, h, which partly overlaps the arc-shaped end of the lever 6. a The side of this extension facing the periphery of the said arc-shaped end is beveled in the form of a gable roof, as shown at h h, In the free space left between these beveled surfaces h and the lever e I locate a roll 1' (or a ball) of such "a diameter, that it has a slight play at the place where the two beveled surfaces meet each other, but is clamped between the parts e and h when moving out of this position, as will bereadily 8o understood by a glance at Fig. 2 of the drawings. I also secure to the frame of the machine an adj ustable set-screw j, the point of which lies in the path in which the rollqlmoves together with the lever g. A spring f 0011- stantly tends to raise the roll 1'.

The head 0 carrying the awl c (which is not shown in Fig. 2) and the head d carrying the needle 61' (shown onlyin Fig. 1) are loosely pivoted on the shaft 1) and oscillate to and c fro, being impelled by the slotted cranks -0 and 01 and the levers c and 01 respectively, pivoted at 0 and having at one of their ends pins 0 d working in the slots of the cranks 5 CF, and at the other end rolls 0 and d re- 9 5 spectively working in cam-shaped grooves,

which are providedin disks rotated together with the main shaft Ct.

I will now describe the thread-guide and the means for imparting an oscillating motion to the same. The pivot of the lever carrying the thread-guide, according to my present invention, is located at is, between the shafts a and b, and as near as possible to the latter. A rocking motion of the lever 71' and the thread-guide is obtained by means of the roll 70 secured at the end of the same, said roll working in a cam-shaped groove I5 similarly to the rolls 9, c and d The threadguide proper 71: is pivoted at k to the lower end of the lever 70 in such a manner that it may swing laterally. The remaining parts connected to the thread-guide are constructed and operated as described in Letters Patent No. 375,244.- This thread guide, I believe to be new and it forms the subject of application for Letters Patent of the United States, Serial No. 488,568, filed by me October 19,1893.

The means for obtaining the lateral oscillation of the shuttle p are the following: The can1-disk g has a grooveq, in which works a roll 7, secured to one end of the lever r, pivoted at r". The other end 4' of the lever 0" has the form of a toothed sector, and engages with a similar toothed sector 8 forming one end of the double-armed lever s, the other end of which is linked to the shuttle 11.

u is a hook oscillating sidewise and operated by means of the camdisk i), the function of this hook being the same as described in the above-mentioned Letters Patent No. 375,244.

The operation of my improved machine, in so far as it differs from the above patented machine, is the following: The set-screwy is adjusted in such a manner that it will stop the movement of the roll alas the lever g approaches its highest position, and thus force the said roll between the lever e and the inclined surface h, so that it will be clamped between these parts and thereby effect a firm coupling between the levers e and g. In consequence thereof, the presser-foot e secured to the former lever will be kept strongly pressed upon the sole and hold the same tightly till the awl c has passed through it. In this moment, when the boot or shoe has to be advanced by the length of a stitch, the lever g is depressed by the cam-disk g, the roll i comes out of contact with the setscrew j, the lovers e and g are momentarily uncoupled, and immediately thereafter the roll t' is raised by the spring f so as to become clamped between the lever e and the upper inclined surface h of the lever g. The levers e and g are thus again coupled with one another. Consequently the lever 6 moves in unison with the lever 9 while the latter continues being depressed by the cam-disk g and the presser-foot e is lifted off the sole. The latter is thus free to be moved laterally as required. When this lateral displacement has taken place, and before the awl o is drawn out of the sole, the lever g is again raised by the cam-disk g and the levers e and g are coupled by the roll 2' striking against the point of the sct-screwj and being thereby clamped between the arc-shaped end of lever c and the lower inclined face h of lever g, as already described. It will be obvious that at each upward and each downward movement of the lever g the latter is momentarily uncoupled from the lever 8. This state is employed for automatically adjusting the presser-foot e to the exact thickness of the sole. As soon as the lever e is uncoupled from the lever g the spring f asserts its power to raise the rear end of lever eand consequently to press the presser-foot 6' upon the sole. Thus an automatic adjustment of the presser-foot e to the thickness of the sole is secured. As the levers c and g are coupled immediately thereafter, the position to which the presser-foot c has been adjusted is preserved invariable till the next adjustment takes place.

The operation of the thread-guide k and its carrying lever 70 will be easily understood without further explanation. In consequence of the particular location of the pivot 70, be

tween the shafts a and b, and as close as possible to the latter, the length of the lever 70 is reduced to a minimum, and it is possible to impart motion to this lever simply by means of a cam-disk anda roll 70 working in a groove k of said cam-disk. The machine, in consequence of this particular arrangement, may be driven at any speed, Whereas the speed was limited in the machines of the same kind used hitherto, owing to the complication of the mechanism for operating the thread-guide.

The mechanism for operating the shuttle p is also a considerable improvement on that described in Letters Patent No. 375,244, and avoids the unsteady movement and rapid wear which occurred when employing the old mechanism. The movement of the shuttle is smooth even in itsextreme positions.

Having thus fully described the nature of my invention, what I desire to secure by Letters Patent of the United States is 1. In a sewing machine of the kind described, a work support, a shaft, a lever pivotally mounted on said shaft and carrying a presser foot, a second or operating lever, one end of which is also pivotally mounted on said shaft, operating mechanism whereby said operating lever is oscillated and a clamp mechanism, one member of said clamp being connected with said operating lever, the other with said presser foot lever, all as and for the purposes set forth.

2. In a machine of the kind described: L11 combination, with the presser-foot e, the lever 6 carrying the same, said lever having an arc-shaped end, and the lever 9 adapted to be operated by a cam-disk g and having a lateral extension is provided with inclines 71/ arranged in the form of a gable roof, of the roll c, the spring f, adapted to eifect the automatic coupling of levers e and g at each In testimony whereof I have signed this downward movement of the latter, the setspecification in the presenceof two snbscrlbxo screwj, adapted to couple the same parts auing witnesses.

tomatically at each upward movement of le- Ver g, and the spring f adapted to effect the PAUL GOHRING' automatic adjustment of the piesser-foot e Witnesses:

to the thickness of the-sole, substantially and HERMANN AUGENREICH,

for the purpose as described. FRANK H. MASON. 

